Gangrene refers to the death of body tissues due to lack of blood flow or infection. It commonly affects extremities like fingers, toes and limbs. There are several types of gangrene including dry, wet, gas and internal gangrene. Gangrene is caused by lack of blood supply, infection, or trauma. Risk factors include diabetes, vascular disease, injury, smoking, obesity and immunosuppression. Symptoms include skin discoloration, swelling, blisters and pain. Treatment involves controlling risk factors, antibiotics, surgery to remove dead tissue, and in severe cases amputation. Prevention focuses on proper diabetes care, weight control, smoking cessation and infection prevention.